1. Field of the Invention
The present invention is related to the field of systems for generating electronic calendars or schedules of events.
2. Background Art
A scheduling or calendaring system is a system for allowing a user to maintain a calendar of events containing information about the event. The event is recorded at entry points in the calendar relating to the date and time of the event. Interactive calendaring/scheduling systems are typically implemented as electronic calendars using data processing systems. The data processing system may comprise a single data processing unit or a plurality of data processing units coupled together. In a multi-user system comprising a plurality of data processing units, users may schedule events on their personal calendars as well as those of other users.
Prior art systems replicate calendars such that each calendar in the enterprise is stored on every server in the enterprise. Thus, each server must store calendar information for the whole system. Further, when any change is made to a calendar, the change must be replicated at each server. Prior art systems also limit a user to defining a finite number of recurrent events. Further, prior art systems store an entry for each of the repeated events, thereby consuming large amounts of storage space.
A prior art system, disclosed in U.S. Pat. No. 4,548,510 issued to Alfred Levine on Oct. 22, 1985, implements an electronic time scheduler for entering and storing daily schedules of events and appointments. The system provides the ability to obtain (i.e., visually or audibly) a daily schedule of appointments, and a subschedule that identifies times-of-day that are still open. The scheduler can be connected to a center data processor. This prior art system does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
Another prior art system, disclosed in U.S. Pat. No. 4,626,836 issued to Donald E. Curtis, et al. on Dec. 2, 1986, is a method of scheduling a meeting between calendar users. An input screen is displayed that contains input fields for entering desired times, dates, and attendees. A comparison is made between this information and the prospective attendees' calendar information. The comparison is between calendar information that is stored in a host system to which the users are connected. Based on the comparison, an option list is displayed to the invitor, and the invitor can select a meeting time. A meeting notice is sent to the attendees. The prior art system of Curtis, et al. does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
A further prior art system, disclosed in U.S. Pat. No. 4,977,520 issued to Harry S. McGaughey III, et al. on Dec. 11, 1990, implements a method of electronic calendaring in a data processing system with a plurality of interactive terminals that facilitates a user's reply to a meeting invitation. An initial notice advises an invitee that a meeting invitation is available for review. A screen can be displayed that contains the details of the meeting along with entries in the invitee's calendar. Based on this information, an invitee can accept or reject the invitation. The prior art system of McGaughey, et al. does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
A further prior art system, disclosed in U.S. Pat. No. 5,070,470 issued to Keith J. Sculley, et al. on Dec. 3, 1991, provides a capability to automatically generate a data stream to request the status of, or automatically schedule a meeting on, a plurality of calendars maintained by an electronic calendaring system. Information associated with a calendaring event is stored in a data structure with fields that are compared with like fields in the plurality of calendars. These calendars may be stored on the user's system, or on a system that is connected to the user's system. Status information for each of the plurality of calendars is stored in multiple data structures. These data structures are transmitted to the user initiating the event. The prior art system of Sculley does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
Still another prior art system, disclosed in U.S. Pat. No. 5,093,813 issued to Alfred B. Levine on Mar. 3, 1992, is an appointment scheduler that has the ability to automatically locate available times based on user preferences and prior commitments. The scheduler may be used locally or remotely via a telephone line. The invention is capable of comparing multiple calendars resident in a single memory store to coordinate a mutually acceptable meeting time. This system of Levine does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
Yet another prior art system, disclosed in U.S. Pat. No. 5,093,901 issued to Charles M. N. Cree, et al. on Mar. 3, 1992, is a method for exchanging entries in multiple calendars resident on an information processing system. One user can schedule an event and invite other users of the same information processing system by sending each of them a notice or request. The current status of each is determined, an entry for the scheduled meeting is automatically entered in their calendars. The prior art system of Cree, et al. does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
A further prior art system, disclosed in U.S. Pat. No. 5,129,057 issued to Gerald C. Strope, et al. on Jul. 7, 1992, is a method of displaying day calendar information in a viewport of a display, and to schedule an event with other users that are interconnected via a local area network. The invention provides for the ability to connect to a host system via a modem hook-up or a network link. The network link provides the ability for network users to communicate. The host system is used to store information for access by all of the network users. The prior art system of Strope, et al. does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
Another prior art system, disclosed in U.S. Pat. Nos. 5,050,077 and 5,197,000 issued to James P. Vincent on Sep. 17, 1991 and Mar. 23, 1993, respectively, provides a method of scheduling events among terminal users of calendaring applications connected to a host system with processing, storage and retrieval capabilities. An event can be scheduled using a prompting screen with fields for entering desired times, dates, and prospective attendees. If the desired times are not available for all of the prospective, the scheduling criteria can be relaxed and the event can be scheduled automatically. The prior art system of Vincent does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
Still another prior art system, disclosed in U.S. Pat. No. 5,199,009 issued to Geno Svast on Mar. 30, 1993, is a programmable reminder clock for storing times, dates and reminder messages for upcoming events. The prior art system of Svast does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.
A further prior art system, disclosed in U.S. Pat. No. 5,220,540 issued to Hiroshi Nishida, et al. on Jun. 15, 1993, implements an apparatus that provides a schedule control function such that a schedule of events are stored in memory at every date and displaying a particular schedule. This invention calculates a present date and time based on a date and time initially set. The prior art system of Nishida does not provide the ability to store repetitive events as one event with an expression for calculating the repetitive occurrences.